The present invention relates to a cooling system for a lubricating system of an internal combustion engine. More particularly, the present invention relates to a cooling system for a lubricating system for an engine for use in powering a water propulsion device of a watercraft.
Personal watercrafts have become very popular in recent years. An enthusiasm for competition has grown with this popularity, and as a result personal watercrafts have become increasingly faster. Many personal watercrafts today are capable of traveling at speeds above 60 mph. To attain such speeds, such watercrafts are typically driven by high power output motors.
Typically, these high output motors are of the internal combustion type and are lubricated with a motor oil as known in the art. Running a motor at a very high output, however, generates a great deal of heat particularly in the lubrication system of the motor. If the motor is continually run in this manner the lubricant""s viscosity will break down and it will not be able to cool the engine properly. The viscosity break down could result in the engine overheating and eventually in full engine seizure.
It is therefore desired to provide a watercraft with a high output engine having a lubricating system which will not overheat and will provide proper lubrication for the engine.
In accordance with the present invention there is provided lubrication cooling system for a high output internal combustion engine particularly suited to watercraft applications. The watercraft is preferably of the personal watercraft variety, having an enclosed engine compartment which is accessible by exposing a maintenance opening under a seat.
The lubrication system includes a lubricant reservoir, means for delivering lubricant to the lubrication system, such as a pump, and a lubrication cooler mechanism comprising a heat exchanger cooled by either forced air or water. In a preferred embodiment of the present invention the engine includes a lubrication collector at a bottom thereof, with a lubricant reservoir mounted in proximity to the engine. In this arrangement, lubricant is supplied from the reservoir through a supply line to a port in the engine. The lubricant passes through the engine to the collector and then flows through the lubrication cooler where it is cooled, as is known in the art. After the lubricant is cooled, it flows back to the reservoir.
In two other embodiments of the present invention, the lubrication cooler is located in the front of the watercraft advantageously in a position to be air cooled by the air forced through an air intake structure located on the front of the watercraft.
In another embodiment, the lubrication cooler is located in the engine compartment within a water jacket. The water jacket is cooled by a water supply from the propulsion unit. In a similar embodiment, the return water is pumped from the water jacket containing the lubrication cooler into a cooling system for the engine.
In an additional embodiment, the lubrication cooler is contoured into a ride plate of a hull of the watercraft and thus is water cooled. In a similar embodiment, the lubrication cooler is located on the inside of the engine compartment with one side exposed to a water inlet area whereby the lubricant is cooled from the ambient water passing thereby.
Further objects, features, and advantages of the present invention over the prior art will become apparent from the detailed description of the drawings which follows, when considered with the attached figures.